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vinegar production

...amount of vinegar containing a mass of vinegar bacteria, called mother of vinegar, was added to start the reaction. One or two small air holes drilled above the liquid level exposed the surface to
aeration. The finished vinegar was drawn off through a wooden spigot near the bottom. Care was taken in refilling the barrel with the new charge of raw ingredients to avoid breaking up the surface...

water supply systems treatment

Aeration is a physical treatment process used for taste and odour control and for removal of dissolved iron and manganese. It consists of spraying water into the air or cascading it downward through stacks of perforated trays. Dissolved gases that cause tastes and odours are transferred from the water to the air. Oxygen from the air, meanwhile, reacts with any iron and manganese in the water,...